Dermatophyte species, microscopic and cultural examination

The dermatophytes Epidermophyton floccosum, Microsporum canis, Trichophyton mentagrophytes var. interdigitale, T. rubrum, and T. verrucosum were compared with respect to the direct microscopic examination of a clinical material and the number of colonies obtained by culture. It was found that the results of microscopy as well as of culture depended to a marked extent upon which species were the cause of the mycosis. The extremes were E. floccosum and T. mentagrophytes var. interdigitale which showed 7.5% and 32.5% isolates with negative microscopic findings and 45.5% and 5.0% isolates with larger than or equal to 10 colonies.